Asymmetric syntheses using the SAMP‐/RAMP‐hydrazone method: ( S )‐(+)‐4‐methyl‐3‐heptanone intermediate: SAMP‐hydrazone (S)‐2 intermediate: (S)‐(+)‐4‐Methyl‐3‐heptanone SAMP hydrazone [(ZSS)‐3] product: (S)‐(+)‐4‐Methyl‐3‐heptanone [(S)‐4] byproduct: nitrosamine (S)‐5

The synthesis of a variety of enantiomerically pure chiral auxiliaries based on (S)‐proline and bearing sterically demanding side chains at the pyrrolidine moiety, such as the secondary amines (S)‐3,5 and 7 and the hydrazines (S)‐6, is described on a molar scale. As key step, the Grignard or RLi addition to the N‐benzylated proline ester (S)‐1 is used.

( S )‐(−)‐1‐amino‐2‐methoxymethylpyrrolidine (SAMP) and ( R )‐(+)‐1‐amino‐2‐methoxymethylpyrrolidine (RAMP), versatile chiral auxiliaries product: ( R )‐(+)‐1‐amino‐2‐methoxymethylpyrrolidine (RAMP) intermediate: hydroxymethylpyrrolidine intermediate: (S)‐(−)‐1‐formyl‐2‐hydroxymethylpyrrolidine. intermediate: (S)‐(+)‐2‐methoxymethylpyrrolidine. intermediate: (S)‐(−)‐1‐amino‐2‐methoxymethylpyrrolidine (SAMP)

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